60results about How to "Brightness unchanged" patented technology

The invention discloses a linear switching constant-current LED drive circuit for control over peak current, and relates to the field of power source drive circuits. Compared with an existing linear constant-current LED drive circuit, and according to the linear switching constant-current LED drive circuit for control over the peak current, an integrating capacitor is connected to a loop of a drive chip in parallel, and average current passing through an LED lamp bead can be kept to be constant through the integrating constant-current mode; in addition, due to the fact that a loop formed by an operational amplifier, a switching selector and a high-voltage power MOS is added to the loop of the drive chip to limit the peak current passing through the LED bead, useless power consumption of a system can be reduced, working efficiency of the system can be improved, heat produced in the working process of the drive chip is reduced, the required rated current of the LED bead can be effectively reduced, the luminous efficiency of the LED bead is improved, the luminous decay of the LED bead slows down, the service life of the LED bead is prolonged, and cost of the system is reduced.

The invention relates to a mining intrinsically safe car backing-up alarming device. More than four middle sound transmission holes, front mounting grooves and rear mounting grooves are formed on the circumference of the inner chamber of a casing; a cable connecting plug is hermetically mounted on a mounting base at the lower part of the casing; a horn is mounted on a rear window of the casing inan inverted manner; a waterproof diaphragm is hermetically mounted on the rear end surface of the casing through a pressure plate; a front cover is mounted at the front part of the casing; a transparent lid is hermetically mounted at a window of the front cover and forms a closed watertight seal cavity; a middle cover plate on which a circuit board, an alarm lamp and a camera are mounted is mounted on the front cover or / and the inner chamber wall of the casing; more than four front sound transmission holes at the front part of an annular groove on the front cover and the middle sound transmission holes on the casing are arranged in a staggered manner; drain holes are formed at the bottom of the annular groove; a rear cover with a spherical surface is mounted at the rear part of the casingand opposite to the waterproof diaphragm; and a cavity between the rear cover and the casing is communicated with the middle sound transmission holes and the front sound transmission holes to form sound channels. The mining intrinsically safe car backing-up alarming device has the advantages of reasonable structure, convenience and reliability in use and flushing resistance, and can dynamically capture video of the rear part of a vehicle.

The invention discloses a brightness adjustment method, device and computer storage medium. The method includes: receiving a mode switching instruction for switching from a first graphics card mode to a second graphics card mode; The current brightness and brightness threshold of the mode; based on the first brightness matching range, the current brightness and the brightness threshold of the first graphics card mode are matched to determine the expected brightness, and the expected brightness is used to characterize the match with the first graphics card mode The standard brightness corresponding to the current brightness; matching the expected brightness based on the second brightness matching range to determine the target brightness of the second graphics card mode; adjusting the screen brightness to the target brightness according to the brightness adjustment rule to maintain the graphics card The screen brightness is consistent before and after switching.

The embodiment of the invention discloses a screen display control method and a mobile terminal, wherein the screen display control method comprises the steps of starting and displaying a control slide block at the first side edge part of the current display screen; if the condition that the control side block slides to the opposite second side edge from the first side edge is detected, lowering the brightness of the first region of the current display screen or the brightness of the second region beyond the first region, wherein the first region is a region in which the control side block passes through when sliding from the first side edge to the second slide edge. The technical scheme provided by the embodiment of the invention has the advantages that the brightness of the local region of the display screen can be regulated according to requirements; the energy consumption is reduced; the energy saving is better realized.